The present disclosure relates to a wavelength division multiplexer, and in particular, to a wavelength division multiplexer including a Bragg grating.
A wavelength division multiplexing (WDM) refers to an optical communication technology for increasing the number of signals to be transmitted through a single optical fiber. Since, in the WDM technology, several different wavelengths are used, it is possible to increase capacity of an optical transmission device by the number of used wavelengths. This makes it possible to reduce cost for a signal transmission system and to construct an efficient network system.
In the fields of optical communication and photonic integrated circuits, many studies have been conducted on the multiplexing and demultiplexing of optical signals. Recently, as an amount of data to be used for data communication increases, the need for research and development of a wavelength division multiplexer is increasing.
At present, an arrayed waveguide grating (AWG), a filter using a Mach-Zehnder interferometer, and an Echelle grating are used as typical WDM devices. To apply the wavelength division multiplexer to more application fields, it is important to reduce fabrication cost of the wavelength division multiplexer as much as possible, and for this, it is necessary to realize a wavelength division multiplexer that can be easily mass-produced. Furthermore, to allow the multiplexing and demultiplexing of optical signals to be performed with high efficiency, it is necessary to conduct a study on the wavelength division multiplexer with excellent optical characteristics.